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From: Greg KH <gregkh@linuxfoundation.org>
To: Deepanshu Kartikey <kartikey406@gmail.com>
Cc: kees@kernel.org, stern@rowland.harvard.edu,
	lgs201920130244@gmail.com, balbi@ti.com, ribalda@kernel.org,
	linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
	syzbot+2ec7fc1793a63864d9d6@syzkaller.appspotmail.com
Subject: Re: [PATCH] usb: gadget: net2280: fix NULL pointer deref in usb_reinit_338x()
Date: Fri, 21 Aug 2026 17:07:09 +0200	[thread overview]
Message-ID: <2026082117-audience-earplugs-ded0@gregkh> (raw)
In-Reply-To: <20260821121220.13006-1-kartikey406@gmail.com>

On Fri, Aug 21, 2026 at 05:42:20PM +0530, Deepanshu Kartikey wrote:
> net2280_probe() only maps dev->llregs when the PLX_PCIE quirk bit is
> set. usb_reinit() dispatches to usb_reinit_338x() for any device that
> doesn't have PLX_LEGACY set, assuming such a device must have
> PLX_PCIE set (and thus llregs mapped). That assumption holds for
> every entry in the driver's pci_device_id table, but a forced driver
> bind (e.g. via sysfs bind/driver_override) can invoke probe() with
> quirks that have neither bit set, leaving llregs NULL and crashing
> in usb_reinit_338x() on the first readl().

What is it with the forced bind patches coming out of the woodwork?  Did
syzbot just decide to go crazy here?

Again, no, this isn't a real issue.  If you try to do a bind to a random
driver, you will get random results, including crashes.  This is a
debugging-only feature for people who want to break their kernels :)

thanks,

greg k-h

  parent reply	other threads:[~2026-08-21 15:07 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-21 12:12 [PATCH] usb: gadget: net2280: fix NULL pointer deref in usb_reinit_338x() Deepanshu Kartikey
2026-08-21 15:05 ` Alan Stern
2026-08-21 15:07 ` Greg KH [this message]
2026-08-22  4:02   ` Deepanshu Kartikey

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